Recently, imaging devices that can pick up a still image while picking up moving images have been proposed. These imaging devices are generally provided with a moving image processing portion for processing image data for moving images that is obtained by reading out signal charges accumulated in a solid-state imaging element such as a CCD (charge coupled device) imaging element, and a still image processing portion for processing image data for a still image that is obtained from signal charges in a similar manner. If a first button for giving an instruction to pick up moving images is pressed, the image data that has been processed by the moving image processing portion is sequentially recorded onto a recording medium. If a second button for giving an instruction to pick up a still image is also pressed while the first button is pressed, the image data that has been processed by the still image processing portion is also recorded onto the recording medium (see JP 2001-103361A, for example).
Conventional imaging devices read out signal charges from all pixels in an imaging element while moving images are picked up, and record and display the moving images by performing a thinning process that reduces the number of pixels in the image data obtained by processing the read out signal charges, in order to improve the quality of a still image that is picked up while the moving images are picked up.
However, in these conventional imaging devices, the frame rate of recorded moving images is low, since the signal charges are read out from all pixels of an imaging element while the moving images are picked up. Consequently, conventional imaging devices cannot pick up moving images showing a smooth movement of a photographic subject, although the quality of a still image that is picked up while the moving images are picked up is improved.
The present invention resolves the above-mentioned problems, and provides an imaging device that can pick up a still image while picking up moving images, in which a high-quality still image can be picked up, and also in which moving images can be picked up at a high frame rate.